title: Chemical mapping of the colorectal cancer microenvironment via MALDI imaging mass spectrometry (MALDI-MSI) reveals novel cancer-associated field effects.
abstract: Matrix-assisted laser desorption ionisation imaging mass spectrometry (MALDI-MSI) is a rapidly advancing technique for intact tissue analysis that allows simultaneous localisation and quantification of biomolecules in different histological regions of interest. This approach can potentially offer novel insights into tumour microenvironmental (TME) biochemistry. In this study we employed MALDI-MSI to evaluate fresh frozen sections of colorectal cancer (CRC) tissue and adjacent healthy mucosa obtained from 12 consenting patients undergoing surgery for confirmed CRC. Specifically, we sought to address three objectives: (1) To identify biochemical differences between different morphological regions within the CRC TME; (2) To characterise the biochemical differences between cancerous and healthy colorectal tissue using MALDI-MSI; (3) To determine whether MALDI-MSI profiling of tumour-adjacent tissue can identify novel metabolic 'field effects' associated with cancer. Our results demonstrate that CRC tissue harbours characteristic phospholipid signatures compared with healthy tissue and additionally, different tissue regions within the CRC TME reveal distinct biochemical profiles. Furthermore we observed biochemical differences between tumour-adjacent and tumour-remote healthy mucosa. We have referred to this 'field effect', exhibited by the tumour locale, as cancer-adjacent metaboplasia (CAM) and this finding builds on the established concept of field cancerisation.
authors.affiliation: Biosurgery and Surgical Technology, Department of Surgery and Cancer, Faculty of Medicine, St. Mary's Hospital, Imperial College London, W2 1NY London, UK.
authors.forename: R
authors.initials: R
authors.lastname: Mirnezami
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Spagou
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: P A
authors.initials: PA
authors.lastname: Vorkas
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: M R
authors.initials: MR
authors.lastname: Lewis
authors.affiliation: Biosurgery and Surgical Technology, Department of Surgery and Cancer, Faculty of Medicine, St. Mary's Hospital, Imperial College London, W2 1NY London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Kinross
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: E
authors.initials: E
authors.lastname: Want
authors.affiliation: Department of Metabolic Profiling, Waters Corporation, Milford, MA 01757, USA.
authors.forename: H
authors.initials: H
authors.lastname: Shion
authors.affiliation: Centre for Pathology, Department of Medicine, Faculty of Medicine, St. Mary's Hospital, Imperial College London, W2 1NY London, UK.
authors.forename: R D
authors.initials: RD
authors.lastname: Goldin
authors.affiliation: Biosurgery and Surgical Technology, Department of Surgery and Cancer, Faculty of Medicine, St. Mary's Hospital, Imperial College London, W2 1NY London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Darzi
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: Z
authors.initials: Z
authors.lastname: Takats
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: E
authors.initials: E
authors.lastname: Holmes
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK; Korrigan Sciences Ltd., 9 Imperial Place, Maidenhead SL6 2GN, UK. Electronic address: ocloarec@korrigansciences.co.uk.
authors.forename: O
authors.initials: O
authors.lastname: Cloarec
authors.affiliation: Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, SW7 2AZ London, UK.
authors.forename: J K
authors.initials: JK
authors.lastname: Nicholson
mesh_terms: D003106:Colon / Q000737:chemistry / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000737:chemistry* / Q000473:pathology*; D006801:Humans; D008055:Lipids / Q000032:analysis*; D012007:Rectum / Q000737:chemistry / Q000473:pathology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D059016:Tumor Microenvironment
chemical_list: D008055:Lipids
keywords: Colorectal cancer; Lipid profiling; MALDI-MSI; Molecular imaging; Tumour microenvironment